Max Hp rating

[Wheelman]

I know most will say to always maximize it for performance or resale value, but I believe there are cases where hp is overrated and torque should be factored as well. Case in point, a Caracal with a 225hp 3.4L V6 is basically the same price as a 200hp 4.6L V8 though the latter makes ~35% more torque even though it makes at most 13% less hp (not sure the 225 is making 10% more than advertised). The Pro XS has better mounts, lower unit and would use more fuel of course feeding the additional cubes though would have a much better holeshot/acceleration and itd be interesting to see how much of a difference in topend if any. The biggest number on the cowling isnt always the best imho, hope that helps someone out there trying to decide.Last edited by Wheelman on August 15th, 2018, 8:20 pm, edited 1 time in total.

[Jstew]

You’re comparing incomparable factors….. If torque was the deciding factor my wife’s 3.5 Ecoboost would be a more feared motor than a Dodge Hellcat by 70 ft. Lbs.. Also delivered with substantially smaller displacement. Torque favors two strokes as well because of double the power strokes per rpm. Take a ride in a 20’ Bullet w/ 225 Pro Max and you’ll truly get a sense of what torque feels like. As much as we’d like to think HP and Torque are in a linear relationship – it just isn’t so.

[Wheelman]

jstew wrote:You’re comparing incomparable factors….. If torque was the deciding factor my wife’s 3.5 Ecoboost would be a more feared motor than a Dodge Hellcat by 70 ft. Lbs.. Also delivered with substantially smaller displacement. Torque favors two strokes as well because of double the power strokes per rpm. Take a ride in a 20’ Bullet w/ 225 Pro Max and you’ll truly get a sense of what torque feels like. As much as we’d like to think HP and Torque are in a linear relationship – it just isn’t so.Im talking about Mercurys two new 4-strokes, the 2-stroke has been discontinued. Though Id actually make the same argument of an old 2.5L 225hp V6 vs 3.0L 200hp V6 on a 1700lb+ boat. Im not sure why youre comparing a 3.5L ecoboost to a 6.2L Hellcat, both of which have forced induction albeit different kinds and Im speaking of two naturally aspirated outboards?

[BIGCATTER]

This could be a BIG can of worms gentlemen . — Seems to me to be a trade off . — Some may agree with you Wheelman , but bigger numbers on the cowel will win out over a long dissertation about torque and horsepower ratings when trying to sell a boat . — I think it would be a fun way to spend time on the water making the comparisons though , with possibly some interesting results . — Hoss

[jignpig]

Wheelman, you brought up that “hp is sometimes overrated and torque should be factored as well.” jstew used your rationale to merely point out that a v6 ecoboost had the capability to produce more torque than a v8 hemi. Regardless of forced air induction vs naturally aspirated engines, he made a point.The new Merc is a change for them. It has taken them several attempts to gain ground on the Yamaha SHO. I know of a particular Bass Cat owner that drove the new Merc as well as the SHO and the G2 at the dealer meetings. Merc did draw closer,possibly even, to the SHO 4 stroke performance wise.Bigger cubes doesnt always mean better either. The question I have is whether or not Merc HAD to go to v8 to get their 4 stroke to be competitive with the v6 Yamaha? Outside of the 250 hp+ Verado supercharged group, their 4 stroke program on bass boats has been sorely lacking, imho.

[Wheelman]

jignpig wrote:Wheelman, you brought up that “hp is sometimes overrated and torque should be factored as well.” jstew used your rationale to merely point out that a v6 ecoboost had the capability to produce more torque than a v8 hemi. Regardless of forced air induction vs naturally aspirated engines, he made a point.The new Merc is a change for them. It has taken them several attempts to gain ground on the Yamaha SHO. I know of a particular Bass Cat owner that drove the new Merc as well as the SHO and the G2 at the dealer meetings. Merc did draw closer,possibly even, to the SHO 4 stroke performance wise.Bigger cubes doesnt always mean better either. The question I have is whether or not Merc HAD to go to v8 to get their 4 stroke to be competitive with the v6 Yamaha? Outside of the 250 hp+ Verado supercharged group, their 4 stroke program on bass boats has been sorely lacking, imho.Not sure which ecoboost he was referring to as they range from 375 ft lbs to 550 ft lbs, the top version coming in the $450k Ford GT which isnt probably what his wife drives though I could be wrong. Regardless the Hellcat makes 650ftlbs in its lowest form, so Im still not following. The Pro Max was 375lbs and the now discontinued 3.0L V6 Pro XS was 505lbs, thats a difference of 130lbs vs the 470lb 3.4L V6 which is only a 35lb difference with the 4.6L V8. Weight is more sensitive on a lighter hull like the Bullet yet a heavier hull is more sensitive to torque, which is whats in comparison. Plus it has 6800rpm limiter which will allow it to run a much smaller pitch prop effectively increasing its acceleration.Thanks for the real world feedback of the different outboards, its not about V8 vs V6 theres only a .4L difference in both DOHC designs and the SHO uses VCT to boost lowend torque to make up for a few less cubes. Im sure Mercury was benchmarking it as well as matching the peak numbers of the outgoing 2-stroke, the V8 sounds so much better than a V6 though the reason for adding 2 cylinders is production costs and a smaller cylinder is easier to control a more efficient burn (i.e. lower fuel consumption). The bore and stroke of their 3.4L is the same as 4.6L V8 like Chevys vortec 4.3L V6 and 5.7L V8.Im curious of feedback on this 200hp 3.5L SOHC V6? Its over 100lbs heavier than the 3.4L DOHC V6 Merc 4-stroke.Last edited by Wheelman on August 18th, 2018, 9:51 pm, edited 1 time in total.

[Jstew]

Hellcat report in car and driver was 707hp @ 6000 rpm and 400 ft. lbs. of torque at 4000 rpm. Accuracy of report is on C&D. Ford ecoboost 3.5l delivers 470 ft. Lbs. but significantly less hp than the hellcat. Torque deliveries are purely in the hands of the developer. The band could be broad or extremely steep and be deliverable and useable at much different places in the power band. The original Ford 4.6 truck motor built all its torque below 2700 rpm. The issue is, torque can be considered formulaic in theory, but is rarely linear with hp. Considering an engine’s torque delivery is too inconsistent as a means of comparison between brands and motor families.

[Wheelman]

jstew wrote:Hellcat report in car and driver was 707hp @ 6000 rpm and 400 ft. lbs. of torque at 4000 rpm. Accuracy of report is on C&D. Ford ecoboost 3.5l delivers 470 ft. Lbs. but significantly less hp than the hellcat. Torque deliveries are purely in the hands of the developer. The band could be broad or extremely steep and be deliverable and useable at much different places in the power band. The original Ford 4.6 truck motor built all its torque below 2700 rpm. The issue is, torque can be considered formulaic in theory, but is rarely linear with hp. Considering an engine’s torque delivery is too inconsistent as a means of comparison between brands and motor families. Hopefully you realize that was a typo as my wifes NA 5.7L Hemi makes 390ft lbs from the factory. Of course valve events and intake runner length will affect the torque curve of an engine(not including exhaust manifolds as theyre pretty much set in stone on an outboard), but on a naturally aspirated engine it is more linear as hp is just a derivative of torque (hp=torque x rpm / 5252). Dad towed the old Classic with the Triton 4.6L 2V in his 97 F-150, the reason it made so much torque down low (90% of peak at 2k rpm where most cruising is done/290ftlb peak@3250) was because its peak hp of 210 was at only 4400rpm. What I believe Mercury is doing with the new V8s is exactly like Yamaha does with the V6 SHO, the engines are identical internally and theyre limiting airflow(think throttle stop/restrictor plate) for the different HP ratings with an electronic throttle body as it appears below since an engine is essentially just an air pump. Ill pose this question to you since you brought up the Bullet, do you think that anyone will be hanging the 225hp 3.4L V6 4-stroke on the back of one being its only 30lbs lighter than the V8? Ranger does offer that outboard on their Z519 surprisingly even though Nitro doesnt on the Z20 which are both max rated to 225hp, but I bet if you put two power poles on that Ranger sled and a 36V trolling motor that it would struggle despite your wallet being over $60k lighter.

[bwp777]

so we just went from boats to cars.that went downhill quickly

[Wheelman]

bwp777 wrote:so we just went from boats to cars.that went downhill quicklyPhysics are the same on land or water, my background happens to be racing cars and hp is great for top speed though torque if youre able to use it wins in acceleration. To quote the late great Carrol Shelby “Horsepower sells cars, torque wins races.”

[Author]

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